Manchester United have reportedly made an inquiry to Chelsea about the availability of midfielder Juan Mata.

The Spain international was linked with a move to Old Trafford earlier this summer, as part of a deal that would see Blues' long-time striker target Wayne Rooney moving in the opposite direction. But the west London club insisted the 25-year-old was not for sale and would not be used in a player-exchange move.

However, according to ESPN, sources from both clubs have now confirmed United have contacted Chelsea regarding Mata's situation, although it is unknown whether it was in relation to the Blues' approach for Rooney or as an independent transfer.

United are plotting a move for Mata (Reuters)

Mata is known to be one of Chelsea owner Roman Abramovich's favourite players and was the club's standout performer last season, with 20 goals and 35 assists in all competitions. However, new manager Jose Mourinho is not understood to be very keen on the Real Madrid product and the report claims the Portuguese tactician is open to selling the playmaker, if it helps the club in landing a talismanic striker.

Also, after Chelsea reportedly hijacked Tottenham Hotspur's move for Anzhi Makhachkala midfielder Willian and opened talks with the Brazilian regarding a potential switch to Stamford Bridge, Mata's place in the club's line-up looks to be in jeopardy.

The Blues already have an overdose of attacking midfielders and wingers in their ranks, with Eden Hazard, Oscar, Kevin de Bruyne, Mata, Andre Schurrle and Victor Moses all competing for the three attacking midfield roles behind the lone striker.

Mata did not feature prominently in Chelsea's pre-season matches, partly due to his involvement in the 2013 Confederations Cup, and was an unused substitute in the club's Premier League season opener against Hull City last week. The former Valencia star was also withdrawn after 65 minutes against Aston Villa on Wednesday.

The report suggests striker Romelu Lukaku is also a potential makeweight in any deal for Rooney but his exit from Chelsea seems unlikely at the moment, with fellow forward Fernando Torres continuing to struggle for form and Demba Ba understood to have fallen out-of-favour.